001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2013, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * -----------------------
028 * AbstractXYZDataset.java
029 * -----------------------
030 * (C) Copyright 2004-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited).
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 05-May-2004 : Version 1 (DG);
038 * 15-Jul-2004 : Switched getZ() and getZValue() (DG);
039 *
040 */
041
042package org.jfree.data.xy;
043
044/**
045 * An base class that you can use to create new implementations of the
046 * {@link XYZDataset} interface.
047 */
048public abstract class AbstractXYZDataset extends AbstractXYDataset
049        implements XYZDataset {
050
051    /**
052     * Returns the z-value (as a double primitive) for an item within a series.
053     *
054     * @param series  the series (zero-based index).
055     * @param item  the item (zero-based index).
056     *
057     * @return The z-value.
058     */
059    @Override
060    public double getZValue(int series, int item) {
061        double result = Double.NaN;
062        Number z = getZ(series, item);
063        if (z != null) {
064            result = z.doubleValue();
065        }
066        return result;
067    }
068
069}